Device for making flexible strips consisting of a continuous metal wire so wound as to form a plane helical spring



May 9, 1961 J. LECLABART 2,983,301

DEVICE FOR MAKING FLEXIBLE STRIPS CONSISTING OF A CONTINUOUS METAL WIRESO WOUND AS TO FORM A PLANE HELICAL SPRING Filed June 29, 1959 5Sheets-Sheet 1 Fig.1

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y 1951 J. LECLABART 2,983,301

DEVICE FOR MAKING FLEXIBLE STRIPS CONSISTING OF A CQNTINUOUS METAL WIRESO WOUND AS TO FORM A PLANE I-IELICAL spam;

Filed June 29, 1959 3 Sheets-Sheet 2 y 1961 J. LECLABART 2,983,301

DEVICE FOR MAKING FLEXIBLE STRIPS CONSISTING OF A CONTINUOUS METAL WIRESO WOUND AS TO FORM A PLANE HELICAL s am:

Filed June 29, 1959 3 Sheets-Sheet 3 United States Patent .DEVICE FORMAKING FLEXIBLE STRIPS CON- SISTING' OF A CONTINUOUS METAL WIRE SO AS TOFORM A PLANE HELICAL Jean Leclabart, 53 Ave. Raymond Poincare, Paris,France Filed June 29, 1959, Ser. No. 823,552

Claims priority, application France Mar. 9, 1959 6 Claims. (Cl. 153-65)for wire initially bent by passage tangentially into the cylinder,around the cylinder and tangentially therefrom, and a guide movablebetween a first position defining with the outlet a path for partiallystraightening wire emerging from the cylinder and a second positionsetting emerging wire to the form required between adjacent turns of thehelix.

A method of embodiment of a device according to the invention, and theway in which the device works, are illustrated in very diagrammaticfashion in the appended drawings.

In the drawings:

Figure 1 illustratm an elevation of the device, sectioned along II inFigure 2;

Figure 2 is partially cut away plan view, sectioned along H-H in Figure1;

Figure 3 is a plan view extracted from Figure 2, showing how the controlcams are arranged;

Figures 4, 5 and 6 are working diagrams showing operational cycle of thedevice;

Figure 7 is an overall perspective view of the device;

Figure 8 is an enlarged view of the spindle and the cup therein as shownin Figs. 1 and 2.

As shown in Figures 1 and 2, the metal wire 1, introduced through afixed guide 2, is inserted between two drums 3 and 4. v

The drum 3 is rotationally fast with a vertical spindle 5 which isrotationally driven by means of a crank 6 fitted to the lower end of thespindle 5. Rotation of the drum 3 is transmitted to the drum 4 by way oftwo spur pinions 7 and 8, which are respectively fast with the twodrums, and have pitch diameters equal to the diameters of the drums. Thedrum 4 is mounted on a vertical shaft 9 carried by a lever 10, which isarticulated about a fixed spindle 11 and acted on by a spring 12 in sucha direction as to cause the drum 4 to bear against the drum 3, thusproviding the grip required to'drive the wire 1.

After passing between the two drums 3 and 4, the wire 1 is guided in agroove 13 in a support 14 attached to a vertical spindle 15. At the topof this spindle there is a cylindrical cup 16, of diameter d, and of adepth slightly greater than twice the diameter of the wire 1. As shownin Figures 2 and 8, the cup 16 is tangential to the direction of thewire 1, which, upon leaving the groove 13, is guided into a rectilineargroove 17 in the spindle 15; the wire 1, after having formed the helicalturn forced by the cup 16, emerges from the latter via a flared aperture18 in the spindle 15. A plate 19, preferably made of transparentmaterial, and detachably fixed to the spindle the 15 and the support 14,prevents the wire 1 from escaping upwards.

A sleeve 20 is centred on the spindle 15, and has attached to it, bymeans of screws 21, an arm 22 which carries at its free end two co-axialrollers 23 and 24 mounted on a common spindle 25, above and below thearm 22 respectively.

The rollers 23 and 24 co-operate respectively with two cams 26 and 27which are locked to the shaft 5.

Each of the two cams comprises a cylindrical profile of radius R and acylindrical profile of radius r, the two cylindrical profiles of one andthe same cam being connected by two straight profiles F and f extendingsubstantially along radii of the cylindrical profiles, and including anangle a between them. The respective angular settings of the two camscause there to be an angle [3 between the profile f of one of the camsand the profile F of the other cam (Figure 3).

The sleeve 20, which is acted on by a spring 28 in such a direction asto cause the rollers 23 and 24 to bear against the earns 26 and 27,carries a vertical finger 29 against which the wire 1 bears afteremerging from the aperture 18.

Operation of the device is diagramatical-ly illustrated in Figures 4 to6, wherein the only cam profile illustrated, for the sake of greatersimplicity, is that produced by definite angular setting of the twoearns 26 and 27.

In the phase illustrated in Figure 4, the angular direction of thesleeve 20, and consequently of the guide finger 29, is defined by therollers 23, 24 bearing against the profile R of the cams 26, 27. Adiameter D of the helical turn corresponds to this position of thesleeve 20, and is that assumed by the wire 1 after it has been initiallybent to the diameter d in the cup 16, and then straightened to adefinite extent by passing in front of the finger 29.

Formation of a helical turn of diameter D continues until the instant atwhich the cam has reached the position illustrated in Figure 5. As soonas the roller clears the end of the profile R, the action of the springcauses the sleeve 20 to rotate about the spindle 15 as far as an angularposition defined by the roller bearing against the profile r of the cam.In this angular position of the sleeve 20, which is maintained until theinstant at which the profile F of the cam causes the roller to move backup to the profile R (Figure 6), the finger 29 acts on the wire 1 in thedirection of additional straightening, which defines an arc of a turn ofradius A downstream of the finger 29.

Finally, after the roller has moved back up to the profile R, the wire 1will form a new turn of diameter D.

The pitch between two helical turns of diameter D may be altered byadjusting the angular displacement between the two cams 26 and 27, andthe corresponding variation in the angle 5 defines the straighteningperiod corresponding to the arc of radius A; moreover, adjustment of theangular setting of the arm 22 with respect to the finger 29, which isallowed by the oblong holes in the flanges of the arm 22 through whichthe screws 21 pass, enables the two angular positions of the finger 29with respect to the centre of the cup 16 to be simultaneously varied,with a consequent variation in the amplitude of straightening obtained.

The device which has just been described could natwrally be modified indetail, or supplemented by any useful accessory, without departing fromthe scope of the invention.

What I claim is:

1. In a device for producing a helix from wire, wire feeding means, acylinder receiving wire from said feeding means, an outlet from saidcylinder for wire initially bent by passage tangentially into saidcylinder, then circumferentially around said cylinder and thentangentially out of said cylinder, and a guide for the wire movablebetween a first position in line with the axis of said outlet forpartially straightening wire emerging from said cylinder and a secondposition setting emerging wire into successive'helicoidal turns havingtheir centers displaced from one turn to the next.

, 2. In a device for producing a helix from wire, a pair of wire feedrollers, means for mechanically driving said rollers, means forresiliently biasing said rollers toward one another, a cylinderreceiving wire from said rollers, an outlet from said cylinder for Wireinitially bent by passage tangentially into said cylinder, thencircumferentially around said cylinder and then tangentially out'of saidcylinder, and a guide for the wire movable between a first position inline with the axis of said'outlet for partially straightening wireemerging from said cylinder and a second position setting emerging wirein successive between a first position in line with the axis of saidoutlet for partially straightening wire emerging from said cylinder anda second position setting emerging Wire in successive helicoidal turnshaving their centers displaced linearly from one turn to the next.

4. In a device for producing a helix from wire, a pair of wire feedingrollers, means for mechanically driving said rollers, means forresiliently biasing said rollers towards one another, a cylinder forreceiving wire from said rollers, an outlet from said cylinder for wireinitially bent by passage tangentially into said cylinder, thencircumferentially around said cylinder and then tangentially out of saidcylinder, and a finger guide angularly movable relative to the axis ofsaid cylinder between a first position in line with the axis of saidoutlet for partially'straightening wire emerging from said cylinder anda second position setting emerging wire in successive helicoidal turnshaving their centers displaced from one turn to the next.

5. In a device for producing a helix from wire, wire feeding means, acylinder for receiving wire from said feeding means, an outlet from saidcylinder for wire initially bent by passage tangentially into saidcylinder, then circumferentially around said cylinder and thentangentially out of said cylinder, and a guide movable between a firstposition in line with the axis of said outlet for partiallystraightening wireemerging from said cylinder and a second positionsetting emerging Wire in successive helicoidal turns having theircenters displaced from one turn to the next, said means for moving saidguide comprising a cam rotated by said wire feeding means and twocircular profiles'of difierent diameters on said cam successivelyoperating said guide for each revolution of said cam, each profilecorresponding to one of the two positions of saidguide.

6. In a device f r producing a helix from wire, wire feeding means, acylinder for receiving wire from said feeding means, an outlet from saidcylinder for wire initially bent by passage tangentially into saidcylinder, then circumferentially around said cylinder and thentangentially'out of said cylinder, and a guide movable between a firstposition in line with the axis of said outlet for partiallystraightening wire emerging from saidzcylinder and a second positionsetting emerging wire in successsive helicoidal turns having theircenters displaced from one turn to thenext, said means for'moving saidguide comprising two cams, a single cam follower and twocircularprofiles for each of said cams, said two profiles on each of said camscorresponding to the two positions of said guide, said cams beingmovable angularly relative to one another to vary the profile presentedto said follower.

References Cited in the file of :this patent UNITED STATES PATENTS

